Oil Consumption No Better
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Racer
Joined: Feb 2021
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From: PA
Interesting topic. Mine has been under CPO maintenance until now, so I'm going to check it.
On some vehicles you're not supposed to push the dipstick into its fully seated position to check the oil, rather, just sort of drop it in and let it rest in place . What's the procedure for our dipstick?
On some vehicles you're not supposed to push the dipstick into its fully seated position to check the oil, rather, just sort of drop it in and let it rest in place . What's the procedure for our dipstick?
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From: MA
As posted above, my first oil change was at 4850 miles. Had added 1/2 quart during that 4850 mile interval. Your car sounds like it’s behaving as mine has been. If that’s the case, you’ll probably not make it for 6 months of driving without adding oil. Just keep a record of how much you have added and with how many miles.
Incidentally, the conventional wisdom seems to be that the traditional 1,000 mile oil change is no longer necessary. So maybe pass on it to not further confuse the situation.
For what it’s worth, three different Lexus experts and one experienced independent mechanic insist this is modest oil consumption, if it doesn’t get a lot worse, is not a problem. Will probably go away over time. If not, just the nature of many modern cars using latest automotive technology.
Incidentally, the conventional wisdom seems to be that the traditional 1,000 mile oil change is no longer necessary. So maybe pass on it to not further confuse the situation.
For what it’s worth, three different Lexus experts and one experienced independent mechanic insist this is modest oil consumption, if it doesn’t get a lot worse, is not a problem. Will probably go away over time. If not, just the nature of many modern cars using latest automotive technology.
Intermediate
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From: WI
Lexus Test Driver
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From: NJ
lawnmowers as well typically have the stick that screws in and the instructions specifically say DO NOT screw it in to check level. Same for my snowblower.
Racer
Joined: Jan 2004
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From: North Carolina
I was referring more to cars for my post. My boat does have 2 volvo penta 8.1 liter engines that do have the screw in dip stick and the manual reads Remove the dipstick. The oil level must be between the two marks on the dipstick C. Add oil as necessary so it must be screwed in for proper level. Every manufacturer does this different so best to always read the manual. It does make more sense not to have to screw it back in though.
Lexus Test Driver
Joined: Jun 2014
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From: MI
Interesting topic. Mine has been under CPO maintenance until now, so I'm going to check it.
On some vehicles you're not supposed to push the dipstick into it's fully seated position to check the oil, rather, just sort of drop it in and let it rest in place . What's the procedure for our dipstick?
On some vehicles you're not supposed to push the dipstick into it's fully seated position to check the oil, rather, just sort of drop it in and let it rest in place . What's the procedure for our dipstick?
Fully seated, like for all engines in the world.
Thread Starter
Racer
Joined: Feb 2021
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From: PA
Just tried it without pushing the dipstick all the way into the clicked position. The reading was sloppy and imprecise. Arguably maybe 40% down from top (full) dot. Then did it again, this time after clicking dipstick. Reading second time showed oil full, up to the dot.
Gotta’ click it to be accurate.
Gotta’ click it to be accurate.
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Racer
Joined: Feb 2021
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From: PA
I wait a least an hour to be safe. I wouldn’t think all the oil gets back in just 5 minutes. Why is the difference relevant? Why not simply wait for a while before checking?
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From: MA
I'm just going by the owner's manual (the wording is "wait about 5 minutes") and they want you to check it with a hot engine.
I doubt waiting an hour would matter much, but it would be interesting to know. Its all based on thermal expansion of the liquid and how sensitive is it to temperature.
I doubt waiting an hour would matter much, but it would be interesting to know. Its all based on thermal expansion of the liquid and how sensitive is it to temperature.
Last edited by hotwings; Nov 29, 2023 at 08:08 PM.
Thread Starter
Racer
Joined: Feb 2021
Posts: 1,529
Likes: 573
From: PA
I'm just going by the owner's manual (the wording is "wait about 5 minutes") and they want you to check it with a hot engine.
I doubt waiting an hour would matter much, but it would be interesting to know. Its all based on thermal expansion of the liquid and how sensitive is it to temperature.
I doubt waiting an hour would matter much, but it would be interesting to know. Its all based on thermal expansion of the liquid and how sensitive is it to temperature.
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From: MA
I'm an Engineer so I get curious about this sort of stuff even though thermodynamics was not my field. One of these days when I get the oil level back to full I will run a test to check the level cold and hot to see how much of a difference it makes. Waiting an hour in my opinion should not matter unless its really cold out.
Older cars never seemed to matter as far as what temperature you checked the oil, it never changed at least that has been my experience. Some of the newer cars specify to check it hot. Maybe the thinner oils used today have a greater coefficient of thermal expansion.
I found this on the web which explains it mathematically (remember derivatives in calculus?):
In the general case of a gas, liquid, or solid, the volumetric coefficient of thermal expansion is given by
Older cars never seemed to matter as far as what temperature you checked the oil, it never changed at least that has been my experience. Some of the newer cars specify to check it hot. Maybe the thinner oils used today have a greater coefficient of thermal expansion.
I found this on the web which explains it mathematically (remember derivatives in calculus?):
In the general case of a gas, liquid, or solid, the volumetric coefficient of thermal expansion is given by
Last edited by hotwings; Nov 29, 2023 at 10:12 PM.